For years, I used some older "stadium seats" (for use on the bleachers @ games) that have folding backs. Still have a couple pair of them.
Then, about 10 years ago, I switched to "turkey seats" w/folding legs & no back support.
Finally, about 6 years ago, while @ a garage sale, I found an old Fenwick "Fisherman's seat". It was still like new, & only a couple dollars, so I bought it.
It's convenient, since it's not only a stool, but I can store my lanyard of calls; my facemask/gloves; extra ammo; ect., inside of it.
Possibly not the easiest to carry, although it has a handle in the lid/seat.
And I've always toyed w/idea of putting some foam on the seat, for those extra-long stand waits.
But, considering I'm overweight, & have both bad back & knees, it is a lot better then trying to get down/up off the ground, like I used to.
Stool sits about 16" high, seat's approx 12" x 7" wide.......
After seeing huntsman22's "milk stool", I remember when he was making it & posting pics.
But, I had forgotten about it.
For something "light" & simple to carry/use, I think it's a great idea.
I just might have to make a version for myself, one of these days...although much stouter, w/bigger seat.LOL